The invention relates to a drive for opening and closing a cover member in a motor vehicle.
The cover member is provided especially as a cover member of a glove compartment or other storage compartment in a motor vehicle and/or as a covering for a car radio, CD player or some other similar device built into the motor vehicle. Operating elements of the motor vehicles can be incorporated in the cover member, such as, for example, controls or switches for seating-heating, a warning light system and the like, that have to be, or should be, accessible at all times, that is to say when the cover member is open and when it is closed. The cover member is in principle closed and is opened only as required, for example at the touch of a button, by an electric motor so that in the event of an accident no objects can fall out of the storage compartment.
The drive according to the invention comprises an electric motor that moves the cover member, which is also associated with the drive, by way of a path transmission element, for example a pushing and pressure-applying rod. The problem arises, for example in the event of a power failure, defective control of the drive, a defect in the electric motor or in a reduction gear system, when present, that the cover member cannot be opened. It may be important, however, to be able to open the cover member also in such cases in order, for example, to be able to remove objects contained in a storage compartment that is closed by the cover member, such as important medication, documents or the like.
Accordingly, it is an object the present invention to provide a drive for opening and closing a cover member in a motor vehicle, which avoids the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide the drive for opening and closing the cover member in a motor vehicle, such that it is possible to open the cover member when the drive fails.
In keeping with these objects and with others which will become apparent hereinafter, one feature of present invention resides, briefly stated, in a drive which has a disconnecting device, which disconnects the cover member from the electric motor when a predetermined force acting upon the cover member is exceeded. As a result, the cover member can be opened by hand without movement of the electric motor. The disconnecting device according to the invention, for example, can disconnect the path transmission element from the electric motor or may disable the path transmission element itself.
The invention has the advantage that the cover member can be opened by hand independently of the electric motor. A further advantage of the invention is that the disconnecting device forms an overload protection for the electric motor, which disconnects the cover member from the electric motor if the cover member becomes jammed when the electric motor is running.
The disconnecting device can, for example, be in a form providing frictional engagement and can transmit a limited force or a limited moment normally sufficient to open and close the cover member. In an embodiment of the invention, a detent element is provided as disconnecting device, which disengages when the predetermined force is exceeded and as a result disconnects the drive of the cover member mechanically from the electric motor. This has the advantage that the force required for disconnection can be set relatively precisely and can be maintained in mass production. A further advantage is that, after the detent element has disengaged, the cover member can be moved smoothly. There is also the advantage that the detent element can be re-engaged after the drive has been rectified, and the drive according to the invention is not damaged as a result of the predetermined force being exceeded.
In a special embodiment of the invention, the path transmission element comprises a lever that converts a rotational movement of the electric motor into a translational movement for opening and closing the cover member. At the same time, that lever forms the disconnecting device that disconnects the cover member from the electric motor when the predetermined force is exceeded
In a development of the invention, the lever is in the form of a detent element.
In an embodiment of the invention, the detent element comprises a detent body, for example a ball or a pin, which is pressed into a detent notch by a spring element. By overcoming a detent force, the detent body can be disengaged from the detent notch, as a result of which the cover member is disconnected from the electric motor.
In an embodiment of the invention, the drive comprises an insert that is guided displaceably in the manner of a drawer. The insert forms, for example, a storage compartment or a seat for installation a car radio, CD player or the like. The insert can be displaced by the electric motor especially by way of the lever explained above. The insert forms a path transmission element that transmits a drive movement of the electric motor to the cover member, which is connected pivotably to the insert. The cover member comprises a guiding element that moves it sideways when the insert is displaced to a pulled-out position. xe2x80x9cMoved sidewaysxe2x80x9d means that the cover member is moved to a position in which the insert is accessible. For that purpose, the cover member can be moved upwards, downwards or sideways. When the insert is pushed in again, the cover member moves back to a closed position in which it covers the insert. That construction of the invention can be achieved together with the disconnecting device according to the invention or without it.
In an embodiment of the invention, the cover member has at least one arm by way of which it is connected pivotably to the insert, for example by means of a pin connection. By way of the pin connection, the cover member can be driven by displacement of the insert.
In a preferred construction, the cover member comprises a slide-type guiding element. A slideway preferably extends at an angle relative to the direction of displacement of the insert and as a result causes the desired sideways movement of the cover member when the insert is pulled out. On insertion of the insert, the slide-type guiding member moves the cover member back to the position in which it closes the insert. The slideway does not have to be straight; for example, it can extend in a curve. The slideway can be arranged in a fixed position, for example in a housing in which the insert is displaceably accommodated. The slideway can also be arranged in the arm of the cover member, and a fixed-position sliding pin, sliding block or the like engages in the slideway.
The invention will be explained hereinafter in greater detail with reference to an embodiment shown in the drawings.